FIG 4.
YejM protects cells from LapB toxicity. (A) Serial dilutions of wild-type cells with the integrated lapB overexpression plasmid pEMF53 (Plac::lapB) and either pEMF57 (Para::gfp), pEMF54 (Para::yejM), or pEMF68 (Para::yejM-ΔC) were plated on LB agar with 0.2% arabinose and additionally supplemented with 100 μM IPTG, as indicated. Note that lapB-induced toxicity is relieved by yejM coexpression. (B) LpxC immunoblot. Extracts from WT cells harboring a Plac::lpxC plasmid (pPR111) grown with (lane 2) or without (lane 1) IPTG were used as a marker for the LpxC band. LpxC was also detected in extracts of MG1655(attHKEMF53) [WT(Plac::lapB)] cells harboring either pEMF57 (Para::gfp) (lanes 4 and 5) or pEMF54 (Para::yejM) (lanes 6 and 7) grown in LB containing 0.2% arabinose without (lanes 4 and 6) or with (lanes 5 and 7) 100 μM IPTG to induce lapB expression.